/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

/**
 * @author Alexander Y. Kleymenov
 */

package org.apache.harmony.security.x509;

import java.io.IOException;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

import org.apache.harmony.security.asn1.ASN1SequenceOf;
import org.apache.harmony.security.asn1.ASN1Type;
import org.apache.harmony.security.asn1.BerInputStream;
import org.apache.harmony.security.internal.nls.Messages;

/**
 * The class encapsulates the ASN.1 DER encoding/decoding work with the CRL
 * Distribution Points which is the part of X.509 Certificate (as specified in
 * RFC 3280 - Internet X.509 Public Key Infrastructure. Certificate and
 * Certificate Revocation List (CRL) Profile.
 * http://www.ietf.org/rfc/rfc3280.txt):
 * 
 * <pre>
 *  CRLDistributionPoints ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint
 * 
 *  DistributionPoint ::= SEQUENCE {
 *        distributionPoint       [0]     DistributionPointName OPTIONAL,
 *        reasons                 [1]     ReasonFlags OPTIONAL,
 *        cRLIssuer               [2]     GeneralNames OPTIONAL 
 *  }
 * 
 *  DistributionPointName ::= CHOICE {
 *        fullName                [0]     GeneralNames,
 *        nameRelativeToCRLIssuer [1]     RelativeDistinguishedName 
 *  }
 * 
 *  ReasonFlags ::= BIT STRING {
 *        unused                  (0),
 *        keyCompromise           (1),
 *        cACompromise            (2),
 *        affiliationChanged      (3),
 *        superseded              (4),
 *        cessationOfOperation    (5),
 *        certificateHold         (6),
 *        privilegeWithdrawn      (7),
 *        aACompromise            (8) 
 *  }
 * </pre>
 */
public class CRLDistributionPoints extends ExtensionValue {

	public static CRLDistributionPoints decode(byte[] encoding)
			throws IOException {
		final CRLDistributionPoints cdp = (CRLDistributionPoints) ASN1
				.decode(encoding);
		return cdp;
	}

	private final List distributionPoints;

	private byte[] encoding;

	/**
	 * Custom X.509 decoder.
	 */
	public static final ASN1Type ASN1 = new ASN1SequenceOf(
			DistributionPoint.ASN1) {

		@Override
		public Object getDecodedObject(BerInputStream in) {
			return new CRLDistributionPoints((List) in.content, in.getEncoded());
		}

		@Override
		public Collection getValues(Object object) {
			final CRLDistributionPoints dps = (CRLDistributionPoints) object;
			return dps.distributionPoints;
		}
	};

	public CRLDistributionPoints(List distributionPoints) {
		if ((distributionPoints == null) || (distributionPoints.size() == 0)) {
			throw new IllegalArgumentException(
					Messages.getString("security.17D")); //$NON-NLS-1$
		}
		this.distributionPoints = distributionPoints;
	}

	public CRLDistributionPoints(List distributionPoints, byte[] encoding) {
		if ((distributionPoints == null) || (distributionPoints.size() == 0)) {
			throw new IllegalArgumentException(
					Messages.getString("security.17D")); //$NON-NLS-1$
		}
		this.distributionPoints = distributionPoints;
		this.encoding = encoding;
	}

	/**
	 * Places the string representation of extension value into the StringBuffer
	 * object.
	 */
	@Override
	public void dumpValue(StringBuffer buffer, String prefix) {
		buffer.append(prefix).append("CRL Distribution Points: [\n"); //$NON-NLS-1$
		int number = 0;
		for (final Iterator it = distributionPoints.iterator(); it.hasNext();) {
			buffer.append(prefix).append("  [").append(++number).append("]\n"); //$NON-NLS-1$ //$NON-NLS-2$
			((DistributionPoint) it.next()).dumpValue(buffer, prefix + "  "); //$NON-NLS-1$
		}
		buffer.append(prefix).append("]\n"); //$NON-NLS-1$
	}

	@Override
	public byte[] getEncoded() {
		if (encoding == null) {
			encoding = ASN1.encode(this);
		}
		return encoding;
	}
}
